Boiler-furnace.



TIE. BUTMAN.

BOILER FURNACE.

APPLICATION FILED AUG. 17, 1911.

Patented June 3, 1913.

6 SHEETS-SHEET 1.

Wm. V

- COLUMBIA PLANDORAPH COHWASHINGTON D c T. R. BUTMAN.

BOILER FURNACE;

APPLIOATION FILED AUG. 17, 1911.

1,063,653. Patented Jun 3, 1913.

6 SHEETS-SHEET 3.

Q Ewen/Z57 W W N 7%0vmMBcma/m COLUMNAPLANOORAPH CO., WASHINGTON, D :4

T. R. BUTMAN.

BOILER FURNACE.

APPLICATION IfILED AUG.1 7, 1911.

v Patented- June 3, 1913.

'6 BHEETS-BHEEI 4.

WeedBcZZ rz oLuMmA PLANOGRAPH c0.,wAsH1NuTDN. D. c.

T. R. BUTMAN.

BOILER FURNAGE.

APPLICATION FILED AUG. 17, 1911.

Patented June 3, 1913" I 6 SHEETS-SHEET 5.

@WWKM C'OLUMBIA PLANOORAPH co.,wAsH|Na'roN. n. c.

T. R. BUTMAN.

' BOILER FURNACE.

APPLICATION FILED AUG. 17, 1911.

Patented June 3, 1913.

a SHEETS-SHEET 6.-

Inc/e; 275w mWeed-Bfiwn THOMAS E. BUTMAN, OF MANISTEE, MICHIGAN.

BOILER-FURNACE.

Application filed August 17, 1911.

To all whom it may concern.

Be it known that I, TrroMAs R. BUTMAN, a citizen of the United States, residing at Manistee, in the county of Manistee and State of Michigan, have invented certain new and useful Improvements in Boiler- Furnaces, of which the following is a specification.

My invention relates to improvements in boiler furnaces.

One of the objects of my invention is to provide in a furnace, or stoker, of the class to which it belongs a rotary disk grate, horizontally positioned and adapted to be automatically rotated, whereby a given segment of the grate will pass alternately under the boiler and into a Dutch oven which constitutes part of the furnace structure.

Another object of my invention is to provide an arched Dutch oven in association with the revolving disk grate and coal feeding means, whereby green coal deposited on the grate is coked to a greater or less extent by the radiated heat from the oven arch and while within the oven, and this combustible fuel carried under the boiler, during the time when it is in a condition to radiate the greatest heat, and again taken into the oven at, or about, the time when combustion is substantially completed. And still another object of my invention is to provide means for passing a large quantity of the gases of distillation, from the newly deposited coal, over that part of the grate, and the fuel thereon, that has left the boiler, to vitalize the partly spent fuel so as to equalize the intensity of the heat on the respective sides of the grate, the part entering and the part leaving the boiler.

Other and further objects of my invention will become readily apparent to persons skilled in the art from a consideration of the following description, taken in conjunction with the drawings, wherein;

Figure 1 is a front elevation of my improved furnace, as it appears when associated with and applied to a boiler of the usual water tube type, showing the furnace and boiler fronts. Fig. 2 is a central longitudinal. section of the furnace and boiler combination, showing only a part of the boiler; Fig. 3 is a transverse section of the furnace and part of the boiler setting, taken on line 33 of Fig. 2; Fig. 4 is a broken away portion of the grate showing a partof the ash removing scraper, taken on line Specification of Letters Patent.

Patented June 3,191 3.

Serial No. 644,609.

4% of Fig.2, and not shown in Fig. 3; Fig. 5 is a transverse section through the furnace setting, taken on line 55 of Fig. 2; Fig. 6 is a section taken on line 66 of Fig. 3, showing the coal hopper and feeding means; Fig. 7 is a section taken on line 77 of Fig. 6, showing the means for regulating the coal feeding means; Fig. 8 is a section of a fragment taken above the grate,

showing a modification of the means for.

shifting the coal on the grate and for removing the ashes therefrom; Fig. 9 is a vertical section of a fragment taken on line 99 of Fig. 8; Fig. 10 is a plan view of one of the grate bars, or sections; Fig. 11 is a side elevation of such a bar, or grate, showing the manner in which the coal is deposited upon the grate. Fig. 12 is a section taken on line 1212 of Fig. 8.

In all of the views the same reference characters indicate similar parts.

In the present eXemplificat-ion of my i11- vention I have shown my improved furnace in associated relation with a water tube boiler, of a well known type, wherein 16 is the drum, 17 the depending water tubes, 18 the header and 19 the boiler front. Of course it is equally adaptable to fire tube boilers.

The furnace setting is composed of a centrally disposed supporting pier 2O having a surrounding fire wall 20-, around which the grate is revolved and on which it is partially supported. This pier is preferably located in a central longitudinal plane of the boiler with which the furnace is associated and affords a convenient means for partly supporting the front end of the boiler. A concentric circular inclosing wall 21 substantially encompasses the pier, being provided below the grate with openings 22, 23 and 24- communicating with ash pits 22, 23 and 24, that serve also as air receiving chambers for admission of air un der the grate to pass through the grate and superposed fuel. The openings are covered by doors or closures 25, 26 and 27. These doors are so arranged that they may he slid around in frames so as to vary the extent of the openings for adjusting the admission of air that may pass through the grate and the coal superposed thereon. Such arrangement of doors is clearly shown in Figs. 1 and 5. The ash pits, or air receiving chambers under the grate and be tween the pier 20 and the circular wall 21,

are separated by three radially positioned, separating walls 28, 29 and 30, so that the quantity of air admitted to the fuel upon the grate, or those parts of the grate immediately over the respective airreceiving chambers thus provided, may be independently regulated, to some extent, by the manipulation of these air-admitting doors.

The circular wall 21, or that portion thereof immediately under the boiler, as shown in Fig. 2, extends considerably above the coal-receiving surface of the grate, and acts, to some extent, as a bridge wall as in an ordinary boiler setting, for the purpose of directing the flame and hot gases upwardly toward the depending water tubes of the boiler. The circular wall 21 is flanked near diametrically opposite points thereof by the walls 31 and 32, as of the ordinary boiler setting.

Around the center pier 20 is a wall 20, preferably made of fire brick, to protect the supporting pier 20 from the intense heat of the furnace, just as the walls 31 and 32 protect the respective boiler walls 31 and 32.

The inner lower portion of the wall 21. extends about half way around the furnace setting and under the boiler, but after it leaves the boiler it rises suddenly to the height shown at 21 Fig. 2, near the top of which a fire arch 33 is sprung, which extends from the semi-circular wall 21 to the pier 20, thereby forming what is commonly known as a Dutch oven structure. The arch 33 extends circumferentially around the out side of the furnace pier 20, and ends abruptly on either side, as it enters the fire space under the boiler, or as it comes into conjunction with the side walls 31, 32, in line with the inner surface of the wall 20 of the pier.

At a point a little below the grate level and in the walls 21 is secured a disk plate 35tprojecting inwardly and having at its inner extremity an annular gutter 35 arranged opposite to a corresponding inner disk plate 36, guttered as at- 37, and secured in the pier 20 of the furnace.

38 indicates in general an annular grate, of suitable construction, composed of a series of grate bars, or segments, 39, and preferably providing a central perforated burning area 40 and annular imperforate dead edges 41, and provided with downturned lips, or flanges, 42, loosely fitting into the gutters 35 and 37 respectively of the disk plates 34 and 36 to make an air-sealed joint when the said gutters are filled with ashes. The air spaces that are distributed annularly in the grate bar with varying regularity to provide spaces through which air for combustion may pass, may be adapted to suit the condition required by coal or other combustible fuel superposed upon the grate. This feature of construction will be subsequently referred to when specifically describing some other associated portion of the structure.

The grate may be constructed and braced in any suitable manner, it being my preference to employ a construction substantially conforming with my prior Patents #T2S,3ti2. dated May 19, 1903, and #Wflglilt-l, dated April 11, 1911, such construction as herein shown providing inner and outer annual rims 43 and l-it, connected by radial stay-bars l5 and suitably bridged as with trusses 46, the outer rim having bolted thereto an annular, downwardly facing, toothed rack t7, whereby the grate may be driven in rotation as by m ans of the pinion 48.

I have not herein shown a specific means for rotating the grate as that feature of my invention has been previously described and claimed in the former patents, to which I have herein referred, and is not of present interest. Any means for alfording power may be supplied for the purpose of rotating the grate at proper speed, such as shown, for instance, in my former patents, for driving pinion 49, which is secured to a shaft that is connected with rack-engaging pinion 4-3. For guiding the grate in its proper circular path, a series of horizontally disposed guide wheels 50, mounted beneath the dead plate 34, may be provided to take the lateral thrust of the rack 17.

For feeding green coal to the active or perforate parts of the grate, I provide upon the exterior, or top wall of the oven structure, a feed hopper 51, of such dimensions in height as not to interfere with the opening of the doors in the boiler front 19 of the boiler. lVhen this hopper is used coal may be carried thereto by means of a spout 52, shown in dotted lines, which spout may communicate with a larger hopper, or supply bunker, for a greater supply of coal, and which spout may also be conveniently swung out of the way when it is desirable to open the doors of a boiler front. 19. hen it is desired to shovel the ccal on to the grate by hand the hopper 51 may be removed and coal may be shoveled directly into the chute. communicating with the supper surface of the grate, by hand. From the hopper 51 extends downwardly in a vertical direction a tubular chute at its lower end leading into a fuel chamber 54, included between walls 55 and 56, which extend from the walls of the pier 20 to the outside wall 21. and are superposed several inches above the grate surface, to permit coal to be passed under and to protect the lower portion of the chute from the intense heat of the furnace. The chute 53 terninates at a suitable distance above the grate level, and is preferably provided with an exteriorly operable. feed-adjusting sleeve, or boot, 57, vertically mov able by means of chains 58-5S running over the pulleys 59-59 and connected to a fork 60, mounted on a stem 61, the latter extending through the outside walls 21 and operable for adjustment by means of a nut 62. By this means the feed-adjusting sleeve 57 may be raised and lowered with reference to the chute and a variable quantity of coal may be fed upon the grate. The farther the lower surface of the boot is removed from the upper surface of the grate the greater will be the quantity of coal fed. Decreasing the distance will decrease the quantity of coal.

Upon the cross or radial wall 56 is constructed a protecting wall 63 for the chute 53, but so arranged that there may be provided between the chute 53 and the wall 21, openings 64=6 1 through which the gas distilled from the freshly admitted coal upon the grate, may be caused to pass to the boiler so as to intensify the heat on that side of the grate containing the coal that has passed under the boiler, thereby to equalize the distribution of heat with respect to the side containing the coal which has not yet passed under the boiler and that which has been partially exhausted.

In Fig. 3, it will be noted, that the coal chute 53 is located substantially mid-way between the longitudinal dimension of the grate bar, so that the coal issuing from the chute first will be deposited in a zone sub stantially in the radial center of the grate. In this event a greater proportion of air space should be made in the grate bars near their center region than near their ends, to supply a greater quantity of air in the location where the deposit of coal is the thickest. It is assumed that the grate is traveling in the direction of the arrow. It will be obvious that the coal feeding chute 53 is on one side of a vertical plane taken through the longitudinal center of the structure, and that the coal deposited upon the grate, from the chute, will travel a greater distance to the boiler in the direction of rotation of the grate than is the distance in the opposite direction. As soon as the fuel passes out from under the boot 57 of the chute 53 on to the surface of the grate 38 the heat in the Dutch oven, due to thepractically incandescing walls surrounding the furnace, is so intense that almost immediate distillation of the gases takes place, and by proper manipulation of the air-admission doors 25, 26, and 27, the gases evolved from such distillation may be caused to pass through the spaces 6464, on either side of the chute and over the wall 56, and into the combustion chamber containing the fuel that is already in an advanced stage of combustion, but still retaining sufficient energy to cause complete combustion of the gases, thereby to raise the temperature of that portion of the furnace in correspondence, to some extent, with the temperature of the other portion of the furnace containing the initial deposit of coal.

In burning a lower grade of coal I have found that substantially complete combustion of all combustible material therein will have taken place when the coal has made one complete circuit with the grate, while other coal richer in volatile matter and of a higher grade and having more thermal capacity and of a coking nature is more eflicient when permitted to make two complete circuits of the grate, I, therefore, provide means adapted for handling coal of differing characteristics. For moving the cinders and ashes of the lower class of coal, which requires only one complete circuit of the grate, I provide a scraper bar 65 superposed immediately above the top surface of the grate and'extending tangentially from the pier to a point 66 and then more abruptly to its terminal end. The end of the bar 65 is perforated as at 67 for free relative movement with the bolt 68 therein, as shown in Fig. 4:. The bolt 68 is secured to the plate 69 which is fixed to the wall 21 of the furnace setting and on the outer end of the bolt is nut 70 to prevent the removal of the bar 65. An open, helical compression spring 71 surrounds the bolt 68 and exerts a yielding' pressure against the end of the bar 65. The inner end of the bar 65 is pivoted to a casting fixed to the pier 20, as at 72, so that as that portion of the grate passing under the bar 65 makes contact therewith through the deposit of ashes and cinders, the bar 65 is given a trembling, or vibratory movement,

as a result of the action of the spring 71, and i the cinders are thereby caused to move more freely in a radial direction from the grate. The abrupt deflection of the end of the bar 65 tends to push the cinder-s immediately out of the cinder door 74. The bar 65 will cause the coal deposited upon the grate to be pushed out of the furnace after it has made one revolution, as will be clearly apparent from the described operation in connection with the representation shown in When it is desirable to have the coal remain upon the grate during the time that the grate is making two revolutions I employ the construction shown in Figs. 8 and 12, wherein an inverted trough or box-like casting, having a perforate wall or bar 75, extends tangentially of the pier 20 and is attached by bolts 77, so that it may be readily and quickly removed when repair or replacement is necessary. It is arranged in inserted position with its open side over the air-admittng perforations in the grate bars 39 so as to result in the passage of air through the grate perforations, into the boxlike casting, and out through the perforations in the vertical bar 7 5, thereby to maintain the bar at a temperature below melting point. Ribs 76 are placed around the edges of plate 7 6 to hold ashes and thus pro tect it from excessive heat. After the coal has made a complete revolution, it now being partially consumed, it makes contact with the bar 75, and is thereby moved radially into a zone farther removed from the axis of the grate and near the outside circumference thereof, and fresh coal is deposited in the place of that which has been so moved and that has been partly consumed. The fresh coal that is being deposited upon the grate is ignited by the coal that has been moved over to a circumferential zone farther removed fro-1n the axis of the grate, immediately after it has been deposited on the grate. In most instances the heat of the incandescing walls of the Dutch oven is sufficient to maintain the coal lighted after the fire has been once properly started, but in some instances it may not be sufficient, especially where the coal is of such a nature as to require a high temperature kindling point. lVhen the coked coal is moved over into another zone it is piled up in such a way as to promote combustion and prevent excess air from passing through the grate bars.

A scraper bar 78, is located with reference to the grate, in a similar manner as the scraper bar 75, and extends in such a direction as to intercept the coal that has made the second rotary excursion on the grate, and serves to remove the ashes or cinders through the door 74. The bar 18 is adjustable in length from the point 7 9, having its outer end secured in the wall 21, as at 80. A longer or shorter bar, as may be required, may be attached to the supporting portion at 7 9.

Fig. 11 shows substantially the nature of the deposit upon the grate, just before the coal has made its second excursion. 81 shows the green coal that has been deposited upon the grate, and 82 shows the coal that has been partially consumed and is about ready to be removed from the grate. The air-admitting perforations in the grate may be regulated to suit these conditions, a greater proportion of perforations to the dead surface thereof being provided under the green coal, as requiring a greater quantity of air, and a less proportion under the deposit from which the gas has been driven out and in which combustion is nearly complete. This feature is of considerable importance when the hi hest efficiency is clesirable.

It is apparent that the scraper bar serves to move the coal, that has been partly consumed, from the inner zone, where it has been deposited from the fuel chute, to the outer zone upon the grate, leaving the grate free for the deposit of fresh fuel from the coal hopper.

Openings 83 and 84, closable by doors 83 and 84, respectively, are made in the circumferential wall 21 of the furnace setting, on a level with the upper surface of the grate for the purpose of initially kindling the fire and for inspection of the interior of the furnace, from time to time, during operation, so as to ascertain the condition of the fire and to determine the proper speed of the grate under the conditions then prevailing.

It will be observed by comparing Figs. 3 and S of the drawings, that when I am using the coal-removing means illustrated in Fig. 8 I locate the coal hopper and chute 5?) in a position radially nearer the central pier 20 than when using the bar (35, as shown in T" l l lg. 3, whereby fresh, green coal may be deposited upon the grate radially near the pier in place of that moved.

Vi hile I have herein illustrated and described a single embodiment of my invention it is evident that many changes may be made, within the scope of the appended claims, without departure from the spirit of the invention.

Having described my invention what I claim is:

1. In a furnace the combination with a boiler and a Dutch oven projecting therefrom, of a rotatable grate adapted and arranged for rotation, partly under said boiler and partly in said oven, means for deposit ing green fuel on said grate at a point thereon nearer the boiler side from which said grate moves than the side toward. which it moves, and means for directing the gases arising from the freshly deposited fuel over the grate through the shortest path to the boiler.

2. In a furnace, the combination with a boiler and a Dutch oven projecting therefrom, of'a rotatable grate adapted and arranged for rotation partly under the boiler and partly in said. oven. means for depositing green fuel on said grate at a point thereon nearer the boiler side from which said gratemoves than the side toward which it moves, means providing a chamber surrounding said depositing means, said chamber-providing means shaped to provide communication from one side to the other side thereof, and means for directing the gases arising from the freshly deposited fuel over the grate through the shorter path so pro vided to the boiler.

3. In a furnace the combination of a rotatable grate adapted and arranged for rotation in a substantially horizontal plane, means for depositing green fuel for combustion at a given radial point thereon, whereby the rotation of Said grate will cause the deposit to lie in a substantially circular zone near the axis of said grate, means in advance of said depositing means for moving fuel. that has been partially consumed into a zone farther removed from said axis, and means to direct the hot gases of combustion over said partly consumed fuel to ignite the freshly deposited fuel.

4:. In a furnace of the class described, a substantially flat grate adapted and arranged for rotation in a horizontal plane, a scraper bar overlying the fuel-receiving surface of said grate extending tangentially from a point near the axis toward the periphery thereof, said bar being boX like in form with its open side confronting the grate and one of its side walls being perforated for passage of air that comes through the grate.

5. In a furnace of the class described, a grate adapted and arranged for rotation in a horizontal plane, a central support, a scraper member having vertical walls providing therebetween a space, and means at the free end of one of said walls for detachably securing the member to a support, the other wall of said member being disposed for abutment of its end against said support.

6. In a furnace of the class described, a substantially flat annular grate adapted and arranged for rotation in a horizontal plane, a supporting pier around which said grate rotates, a hollow open-sided scraper member overlying the fuel-receiving surface of said grate, with its open side presented thereto, and a pin secured to said pier detachably to support said member, said member having a perforation near the end of its forward wall to receive said pin and having its rear wall disposed to abut against said pier.

7. A scraper member of hollow boX like construction having one side open for presentation to the coal-receiving surface of a grate, and a depression in its opposite closed top side for containing heat-insulating ashes, a vertical. side wall being perforated for passage of air therethrough coming in from the grate at the open side of said scraper memher, and a securing member to detachably secure it to a stationary part of the grate structure.

8. In a furnace, the combination with a boiler and a Dutch oven projecting therefrom, of a rotatable grate adapted and arranged for rotation partly under said boiler and partly in said oven, air-current controlling means under said grate operable to admit air to said oven in a section local to the longitudinal center thereof, and means for depositing fuel on said grate at a point thereon within said section nearer the boiler side from which said grate is moved than the side toward which it moves.

9. In a furnace, the combination with a boiler and a Dutch oven projecting therefrom, of a rotatable grate adapted and arranged for rotation partly under said boiler and partly in said oven, air-current controlling means beneath said grate operable to permit passage of air through the grate and into said oven in a section of the oven local to the longitudinal center thereof, means for depositing fuel on said grate at a point nearer the boiler side from which said grate moves than the side toward which it moves, to provide shorter and longer paths for air from said air-current controlling means to said boiler, and means in the shorter path to deflect previously deposited fuel from the zone underlying said depositing means to a zone radially beyond said depositing means for traverse of said previously deposited fuel and the newly deposited fuel, adjacent thereto, through said longer path.

In testimony whereof I hereunto set my hand in the presence of two witnesses.

THOMAS R. BUTMAN.

In the presence of Forum BAIN, MARY F. ALLEN.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents. Washington, D. G. 

